hi all, well, after a long slog, and a few wrong turns, it is all obvious. 9load reads the partition table and writes the disk config. it reads into a 2k buffer but it only reads one sector -512 bytes on my disks, which is not enough for the large number of partitions i have.
the solution is is simple, plan9.ini has a readparts= option which asks the kernel to re-read the partition table and setup devsd again. i assume this was added for just my situation. a fix for 9load would be fairly simple but a better fix might be to use 9front's booting structure... i will fix devfs when i get a chance though, it needs to report errors and attempt to continue in the face of bad configuration lines. -Steve
